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The numerical analysis model of temperature in a roll and a rolled material was first derived by solving the equations of heat conduction. Next, the occurrence limits of heatstreaks for reduction in thickness and interface temperature in a roll bite were evaluated experimentally and numerically in cold rolling experiments of stainless steel (SUS430) with two kinds of lubricants. Also, the thermal stability of two lubricants was measured by thermal balance experiments. Consequently, the limit of interface temperature due to heatstreaks calculated numerically is almost constant in a lubricant, which suggests that an outbreak of heatstreaks is mostly dependent on the thermal stability of lubricant. Also, larger quantity of synthetic ester is considered to give higher heatstreak resistance in cold rolling of stainless steel.

A charging model is proposed for an electret film made of potassium-ion-doped SiO2 that can be formed between the two opposing micro-electrodes of a microelectrostatic actuator, separated by a microscopic gap. On the basis of experimental evidence that charging only occurs in the positively biased electrode during the charging process and that the charging polarity is negative, we assumed that the cause of the electret charges is negatively charged oxygen ions residing in the SiO2 film, which arise as a consequence of potassium ion depletion. This assumption was supported by SIMS (Secondary Ion Mass Spectroscopy) analyses that indicate the presence of a depletion region of potassium ions near the interface of the silicon and the oxide film on the positively biased electrode. Calculations of the charged potential using Poisson's equation with the spatially distributed negative charges in the depletion region showed good agreement with the measured surface potential. It appears that our charging model can consistently elucidate potassium ion electret technology. [ABSTRACT FROM AUTHOR]

Probable masons why some protein crystals grown in a magnet exhibited better quality than control are discussed as follows. (1) Sedimenting three-dimensional nuclei are able to have the same orientation as the underlying, mother crystal into which the nuclei merge. (2) Protein solution may become more viscous, leading to reduction of convection. (3) If an upward force is generated by use of an inhomogeneous magnetic field, the effects of the density differences can be made less significant, causing the reduction of natural convection and the retardation of crystal sedimentation. [ABSTRACT FROM AUTHOR]

Chlorides with different paramagnetic cations such as Ni2+, Co2+ and Mn2+ were used as crystallizing agents instead of NaCl to crystallize hen egg-white lysozyme. NiCl2 was found to give two types of crystals with different morphologies: one (roof-like) is a new type of orthorhombic P212121 crystal with lattice constants a=79.0 A˚, b=80.8 A˚, and c=37.5 A˚; the second is an ordinary tetragonal crystal of its characteristic shape with a=b=80 A˚ and c=38 A˚. The appearance of the roof-like shape became dominant in the presence of a magnetic field. In the case of using CoCl2 and MnCl2, ordinary tetragonal crystals were formed. A striking fact was that the a-axis of the crystals oriented along the magnetic field when CoCl2 was used, as opposed to the usual c-axis orientation. Large and optically perfect lysozyme crystals can be obtained in a magnetic field when NiCl2 or MnCl2 is used as a crystallizing agent. These profound effects of the paramagnetic cations may be caused by the coordination of Ni2+ and Co2+ ions to a lysozyme molecule, which was found by X-ray crystallography. [Copyright &y& Elsevier]